Is there a way of testing the cluster?

[Mechan1k]

Just wondering ... my fuel gauge has been giving me the ИИИИs lately.
It goes from Full to empty and back again (many times per day).
I have been doing extensive testing between the tanks and the loom which goes into the back of the cabin of the ute.

I have re-earthed the loom to make sure it is all working fine.

Another issue I have been having with the cluster is that the backlight on the odometer LCD display has beeing "half working" intermittently ... and now tonight the backlight has died altogether.

The fuel gauge is now showing empty with fuel light on (while the driver's side tank is just under half full and the passenger side tank is full).

The needle on the fuel gauge though lifts slightly when I turn the car on ... but stays within the red region of Empty.

Also when i had the intermittently backlight issue where one side would die ... I'd flick the casing of the cluster right in front of the odometer and the light would flick back on again .... it doesn't respond to this anymore.

Is it a case of get myself another cluster and plug it in and away I go (after getting my odometer reading setup correctly)??? Or can I test it another way.

How cheap do standard SII clusters go for????
And who does the odometer change ... Ford i presume???

Any help is appreciated.